Circuit breaker



E. T. PLATZ CIRCUIT BREAKER May 31, 1949.

3 sheets-shet 2 Filed 0c t. 9, 1944 INVENT OR. ELWOOD T. PLATZ E. T. PLATZ CIRCUIT REAKER 3 Sheets-Sheet 5 INVENTOR. ELWOOD 1'. PLATZ BY ;a Z

May 31, 1949.

Filed Oct. 9, 1944 Patented May 31, 1949 UNITED STATES PATENT OFFICE CIRCUIT BREAKER Elwood T. Platz, Detroit, Mich.,-assignor to Bulldog Electric Products Company, Detroit, Mich.,

a. corporation of West Virginia Application October 9, 1944, Serial No. 557384 11 Claims.

` handles of two switches may .be placed together in alignment.

Flg. 3 is an exploded perspective view showing a handle, and other parts of a switch. V

Fig. 4 is a sectional view as if on line 4-4 of Fig. 1.

Fig. 5 illustrates the cooperation of parts of the device. Fig. 6 is a step by step view showing movement of parts of thedevice.

Fig. 7 is a View illustrating the coaction of the parts, showing the parts in the open circuit position, unlatcl'el.

Fig. 8 shows the parts of Fig. 7 but in a circuit open and relatched position.

Fig. 9 shows the parts of Fig. 7 but with the partsin the closed circuit position.

The multi-polar circuit breaker herein disclosed may `be said to comprise two separate single pole breakers A and B, mounted hack to back. Each comprises a casing lo, having a back closed by a cover H and having a top in which slides a handle il.

When two such breakers, A and B, 'are mounted back to back upon a mounting plate IS, they may be locked in position on such plate by a looking strip !8.

Within the casing -lfl of each breaker is a stationary contact 44 (Flg. 7) adapted to be engaged .for -butt contact by a movable contact 48 formed on the end of a contactor 49, pivotally mounted at 5l by a rivet pin which fastens a bimetal strip 52 to the contactor, and which also pivotally mounts an insulation plate 53, hereafter referred to as a holding plate or translator. Strip 52 is connected by a loop, not shown, to a load terminal to complete the circuit. An oper.- ating spring 55 normally engages a lug 58 of contactor 49, to which contactor the bimetal strip 52 is riveted, and thus holds the hook or latching end 50 of the bimetal strip against the holding or latching edge 5l of the holding plate 53 2 (Fig. 9), but when the hook end '50 is moved oli the edge Bl of the holding plate or translator 53, or unlatched, as by warping of strip 52 on overload, the spring 56 rocks the contactor on its pivot in a manner to move the movable 'contact 48 from 'the stationary contact 44 and open the circuit, and also rocks plate 53 to the open circuit osition. However, when the latch 'at Bli-BI holds, spring 55, biases the contactor 49 upwardly, with plate 53, to the closed circuit posi tion.

The sliding handle has a manual unlatchin g cam 62 which may be moved down by movement of th handle ll to move .the hook end '60 off the' holding edge 5! for unlatching; manual circuit opening movement of the contactor is effected, of

course, by the Operating spring 56.

Unlatching may also be effected automatically, -on overload, by the warping of the bimetal strip 52 in a manner to move the hook end 6! oli the holding edge 50 to unlatch the contactor, whereupon spring 56 will move the contactor. to opencircuit position.

Relatching may be accomplished manually by movement of the handle l'l downwardly or inwardly (Fig. 8) from its normal or "out" position (Fig. 7), whereupon its cam 'll will engage the portion 72 of the holding plate or translator 53 to move the translator downwardly Since the contactor 49 is 'pivotally fastened to the translator 53, at 5l, the contactor rocks clockwise on casing shoulder 41. Both parts 53 and 49 move together, -as well as relatively, on the relatching operation, until the latching end '80 of the bimetal 52 again engagesthe holding edge &I -of the translator 53 .(Fig. 8) whereafter, upon release of the handle, the spring 55 will move the contactor and the translator upwardly (from Fig. 8) to reclose the circuit (Fig. 9).

In a multi-pole breaker, two breakers, each identical to the other, are disposed back to back against the mounting plate 16 and held there by the looking strip !8. Each'breaker handle Il is intended to cooperate with a similar handle on the other `breaker to form a two-*pole handle. Each handle has a dowel pin [50 (Fig. 3) disposed in a hole I5| of the other handle, so that the two dowel pins and the two -h oles line up as the handle's are faced against each other to maintain the handles in alignment.

Seated fiush -in a shallow recess on the side of each handle is a thin insulation sliding link !52 (Figs. 1-3) which is arranged to slide with the handle and also to slide with respect to the handle for lost motion. Link |52 has an opening |53 for receiving a lug 35 of the translator 53. Each link has a hooked upper end !54 which seats in a notch !55 at the end of one leg of a U-shaped equalizing crank 56, through which passes a bushing !51 which joumals the equalizing crank in the handle.

Bushing !51 is hollow, to receive a bolt !58 (Fig.

1) which goes through the 'two handles and I Each handle has not only the resetting ca'm 'H and the manual releasing cam 62, previously mentioned, but also an automatic auxiliary releasing cam !62. i

The operation of the parts is as follows:

Assuming /the devices are assembled properly, with the handles fastened to each other and with the equalizing cranks !56 hooking' to each other, so that there is, in effect, a unitary handle having two sliding links !52 which are connected to each other through the equalizing unit consisting of the two cranks !56, when the handle is moved down from the full "out" or open-circuit position (Fig. 7) for manual closing, then the cams 1! operate on the portions 12 of the translators 53, not only to relatch the contactors to the translators (Fig.- 8), but also to start the movement which ultimately results in the contactors 49 engaging contacts 44, and lugs 35 of the translators being hooked into the openings !53 of the sliding links !52. Now, 'when the handle is released, it is moved outwardly (by outward biasin springs 3!) to the intermediate or circuit-closed position (Fig. 9), as determined by the engagement of lugs 35 and the sliding links !52 which, in eifect, are part of the handle, these links !52 holding the equalizer unit of cranks !56 on opposite sides of the axis of bolt !56, thus holding the handles !1 in the intermediate position.

Now if the handle is pressed down again, the cams 62 of the handle move the hook ends 60 of the bimetals 52 for unlatching, whereupon the contactors 49 will be moved by their springs 56 to the open-circuit position, and whereupon the translators 53 'will also move so that their lugs 35 are released from the openings !53 of the sliding links !52; and when the handle is thereafter released, the handle springs 3!, move the handle out to the full "out" or open-circuit position, holding it there.

A subsequent movement of the handle down causes relatching and reclosing through the section of the cams on the portions '!2 of the translators 53, with handle position being determined to the intermediate or closed position by the engagement of lugs 35 of the translators with openings !53 of the sliding links !52.

For automatic operation it is necessary to start with the handle in the intermediate or circuitclosing position where the lugs 35 hook into the openings !53 of the sliding links !52 (Figure 9) and where the contactors are in circuit-closing position, latched at 60-6!,- and engaged with stationary contacts 44. In the event one of the bimetal strips, let us say the strip of switch A, warps due to overload, it will release or unlatch the contactor 49 of switch A from the translator '53 of switch A, whereupon the spring 56 of switch 4. A will move that contactor to open-circuit position and, at the same time, cause that translator to move and cause its lug to leave the opening !53 in the sliding link !52 of switch A (Fig. 6).

Immediately, the handle, i. e., the unitary handle of both switches, starts to move up. This is permitted by the rotation of the equalizing crank unit on pivot !51 as an axis. This crank unit had been held against rotation, through link 52 of switch A, by the engagement of lug 35 with that link !52;.but when lug 35 left opening !53 of link !52 to release that link, it also released one end of the crank unit, freeing it to rotate. However, the other end of that equalizing unit is still held down by the link !52 of switch B, which at that time is held down by the lug 35 of switch B which is still in the circuit-closing position. However, as the unitary handle moves up, the cam !62 of switch B moves the bimetal of that switch to release at 60-6! or unlatch and thereupon the spring 56 'of switch B will move the contactor 49 of switch B to the open-circuit position and also move the translator 53 of switch B to the open-circuit position, so as to release its lug 35 from the sliding link !52 of switch B.

For reiatching and reclosing thereafter, the handle may be pushed down to cause relatching through the action of cams 1! and portions 12 of the translators 53. Such movement of the handle also causes the equalizer crank unit to level, (if it had been tilted and not previously levelled) due to the bottoming of the ends of sliding links !52 on shelves !63, Fig. 1, and this causes the sliding links !52 to return to the position where they are ready to be engaged by the lugs 35 of the translators 53.

It will be observed that in the construction herein disclosed it is possible to place the two breakers on opposite sides of the center mounting plate !6 with a space between their casings but with the handles !1 engaging each other, face to face, to form, in effect, a unitary handle for the two switches. The switches thus placed may be locked to each other by the locking bolt !56 which passes through the handles to form a unitary two-pole Construction wherein each pole or each switch is on an opposite side of the center mounting plate from the other pole and other switch.

It will also be observed that if. for some reason or other, either because of misalignment of parts or mechanical variation; or because the operator has not pressed the handle down completely, only one pole relatches, the Construction is such that the handle, upon release, will unlatch that pole. In a two-pole breaker, it is important to have both poles relatched and it is undesirable to have only one pole relatched. In the breaker herein disclosed, it is impossible to relatch one pole only because even if one pole were relatched temporarily, as soon as the handle is released, that pole will again unlatch.

Lugs 35 of the translators 53 hold the handle through links '!52 and crank !56 when the parts are in the circuit closed position (Fig. 9) to determine an intermediate or partly "out" position of the handle, this position indicating that the circuit is closed. However, in the circuit open position (Fig. 7), lugs 35 are free of the handle links and the handle is moved to the full "out" position by its spring 3l, and this position indicates that the circuit is open.

It will be observed that when one contactor unlatches, and moves to open position automatically,

it operates to move the other contactor for unlatching, by permitting movement of the handle which has an unlatching cam' for the second contactor, The movement of the first contactor does not directly cause the second contactor to unlatch, but rather the movement of the first contactor permits theactuator or handle to be moved, and it is this movement of the actuator that unlatches the second contactor.

It will also be observed that the movement o the actuator is not caused by the movement of the first contactor Ior unlatching or for opening' the circuit, but is 'rather eaused by the sprin'gs !I of the actuator( However, the movement of the actuator, though not caused by the movement of the first contactor, is determined or controlled by the movement of the first contactor. i

Now having described the circuit breaker herein disclosed, reference should be had to the claims which follow.

I claim:

1. A multipole circuit breaker comprising two contactors, each having its own latching and automatic unlatching means, and its own means for moving it to open circuit position on unlatching and for moving it to closed circuit position on relatching, a unitary handle for the contactors, means responsive to contactor movements to determine two different' handle positions, one for open circuit, i. .e., contactor unlatched, and an-` other for closed circuit, i. e., contactor latched, an unlatching means on the handle whereby when the handle is moved to open circuit position upon unlatching of one contactor-the unlatching means of the handle causes unlatching of the other contactor, and means for permitting the handle to move, upon unlatching of either con tactor, with such handle movement causing unlatching of any latched contactor.

2. A multipole' circuit breaker comprising two contactors, each having *its own latching and automatic unlatching means, and its own means for moving it to open circuit position on unlatching and for moving it to closed circuit position' on relatching, a unitary handle for the contactors, means responsive to contactor movements to' determine two difierent handle positions, one for open circuit, i. e.contactor unlatched, and another for closed circuit, i. e., contactor latched, an unlatching means on'the handle whereby when the handle is moved to open circuit position upon unlatching of one contactor, the unlatching means of the handle causes unlatching of the other contactor, and means for permittingthe handle to move, upon unlatching of either contactor, with such handle movement causing unlatching of any latched contactor; the handle having a relatching means and a manual unlatching means for each contactor, whereby relatching or manual unlatching of both contactors simultaneously may be eflected by manual movement of the handle.

3. A multipole circuit breaker comprising two contactors, each having its own latching and automatic unlatching means, and its own means for moving it to open circuit position on unlatching and for moving it to closed circuit position on relatching, a unitary handle for the contactors, means responsive to contactor movements to determine two different handle positions, one for open circuit, i. e., contactor unlatched, and another for closed circuit, i.- e., contactor latched. an unlatching means on the handle whereby when the handle is moved to open circuit position upon other contactor, and means !or permitting the 'handle to move, uponunlatchlng o! either contactor, with such handle movement causing unlatching of any latched contactor, and a mounting plate for the breaker, the two contactors, their latching and automatic unlatching means, and their means for moving them when'unlatched or relatched, being on opposite sides ot the mounting plate, with the handle straddllng the mounting plate.

4. A multipole circuit breaker comprising two contactors, each having its own latching and automatic unlatching means, and its own means for moving it to open circuit position on unlatching and for moving it to closed circuit position on relatching, a unitary handle for the contactors, means responsive to contactor movements to determine two diflerent handle positions, one for open circuit, i. e., contactor unlatched, and another for closed circuit, i. e., contactor latched, an unlatching means on the handle whereby when the handle is moved to open circuit position upon unlatching of one contactor, the unlatching means of the handle causes unlatching of the other contactor, and means for permitting the handle to move, upon unlatching ofeither contactor, with such handle movement causing unlatching of any latched contactor, the handle having a relatching means and a manual unlatching means for each contactor, whereby relatching or manual unlatching of both contactors simultaneously may be effected by manual movement of the handle, and a mounting plate for the breaker, the two contactors, their latching and automatic unlatching means, and their means for moving them when unlatched or relatched, being on opposite sides of the mounting plate, with the handle straddling the mounting plate.

5. In a multipole circuit breaker, a plurality of contactors, each having a holding .means therefor to which the contactor can be latched, and each having an automatic unlatching means therefor, an actuator having a second unlatching means for each contactor, means for moving the actuator in a contactor unlatching manner, a means controlled by each contactor for releasably holding the actuator when the contactor is in circuit closing position, means for moving each contactor to circuit open position when it is unlatched automatically and thus causing it to release the actuator for contactor unlatching movement, at which time the actuator automati cally unlatches any latched contactor by the action of its unlatching means thereon.

6. In a multipole circuit breaker, a plurality of contactors, each having a holding means therefor to which the contactor can be latched, and each having an automatic unlatching means therefor, an actuator having a second unlatching means for each contactor, means for moving the actuator in a contactor unlatching manner, a means controlled by each contactor for releasably holding the actuator when the contactor is in circuit closing position, means for moving each contactor to circuit open position when it is unlatched automatically and thus causing it to release the actuator for contactor unlatching movement, at which time the actuator automatically unlatches any latched contactor by the action of its unlatching means thereon, and means connecting the actuator and the contactor controlled means that releasably holds the actuaunlatching` of one contactor, the unlatching.

means of the handle causes unlatching of the tor in circuit closing position, said means being constructed in a manner to permit the actuator to move, on automatic unlatching of one conmeans for each contactor, means for moving the.

actuator in a contactor unlatching manner, a means controlled by each contactor for releasably holding the actuator when the contactor is in circuit closing position, means for moving each contactor to circuit open position when it is unlatched automatically and thus causing it to release the actuator for contactor unlatching movement, at which time the actuator automatically unlatches any latched contactor by the action of its 'unlatching means thereon, the actuator moving means being separate from the contactor or the contactor moving means, even though actuator movement is under the control of the contactor through theactuator holding means.

8. In a multipolecircuit breaker, a plurality of contactors, each having a holding means therefor to which the contactor can be latched, and each having an automatic unlatching means therefor, an actuator having a second urlatching means for each contactor, means for moving the actuator in a contactor unlatching manner, a means controlled by each contactor for releasably holding the actuator when the contactor is in circuit closing position, means for moving each contactor to circuit open position when it is unlatched automatically and thus causing it to release the actuatcr for contactor unlatching movement, at which time the actuator automatically unlatches any latched contactor by the action of its unlatching means thereon, the actuator having contactor relatching means.

9. In a multipole circuit breaker, a plurality of contactors, each having a holding means therefor to which the contactor can be latched, and each having an automatic unlatching means therefor, an actuator having a second unlatching means for each contactor, means for moving the actuator in a contactor unlatching manner, a means controlled'by each contactor for releasably holding the actuator when the contactor is in circuit closing position,` means for moving each contactor to circuit open position when it is unlatched automatically and thus causing it to release the actuator for contactor unlatching movement, at which time the actuator automatically unlatches any latched contactor by the action of its unlatching means thereon, the actuator hav- 'ing contactor relatching means, and a connection between the actuator and the holding means 8 therefor whereby contactor relatchlng movement of the actuator causes the actuator holding means to move out of actuator holding position.

10. In a multlpole circuit breaker, a plurality of contactors, each having a holding means therefor to which the contactor can be latched, and each having an automatic unlatching means therefor, an actuator having a second unlatching means for each contactor, means for moving the actuator in a contactor unlatching manner, a means controlled by each contactor for releasably holding the actuator when the contactor is in circuit closing position; means for moving each contactor to circuit open position when it is unlatched 'automatically and thus causing it to release the actuator for contactor unlatching movement, at which time the actuator automatically unlatches any latched contactor by the action of its unlatching means thereon, the actuator having contactor unlatching means for manual unlatching, in addition to the contactor unlatching means for automatic unlatching.

11. In a multipole circuit breaker, a plurality of contactors, each having a holding means therefor to which the contactor can be latched. and each having an automatic unlatching means therefor, an actuator having a second unlatching means for each contactor, means for moving the actuator in a contactor unlatching manner, a means controlled by each contactor for releasably holding the actuator when the contactor is -in circuit closing position,` means for moving each contactor to 'circuit open position when it is unlatched automatically and thus causing it to release the actuator for contactor unlatching movement, at which time the actuator automatically unlatches any latched contactor by the action of its unlatching means thereon, the actuator having contactor unlatching means for automatically unlatching, the actuator being of the push button type, and the parts being so arr'anged that, on successive alternate push in strokes of the actuator, the actuator causes unlatching of the contactor, if it is latched, or relatching of the contactor, if it is unlatched.

' ELWOOD T. PLATZ.

REFERENCES -CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number 'Name Date 970,600 Atwood Sept. 20, 1910 2,099,585 Von Hoorn Nov. 16, 1937 2,343,612 Frank Mar. '7, 1944 &385.727 Platz Sept. 25, 1945 

